Validation of a 3D macroscopic model for superconductors

Purpose - To provide a validation of a three-dimensional (3D) macroscopic model for superconductors comparing numerical to experimental AC losses of a BSCCO-2223 tape subject to an orthogonal magnetic field and a transport current. Design/methodology/approach - We solve in 3D geometries the eddy current problem in presence of superconductors, represented by a power-law characteristic rewritten into a variational form. An integral formulation of the magneto-quasistatic Maxwell's equations is used. The solution of the problem is found by an unconstrained minimization of a suitable functional. The numerical results on AC losses computation are compared to experimental data. Findings - The agreement between numerical and experimental data is good in a wide range of currents and magnetic fields. Research limitations/implications - The magnetic field is assumed to be orthogonal to the tape. Different incidence angles should be taken into account. Practical implications - It is possible to extend the range of validity of the engineering formulae for AC losses used in the work. Originality/value - The paper provides a validation of a numerical code against experimental results: this is always challenging in the field of applied superconductivity.